Allergen avoidance is widely accepted by allergists as a method of controlling rhinitis or asthma related to indoor allergens. Further, the recent NIH guidelines for treatment of asthma recommended that specific allergen avoidance should be adopted as first-line management for allergic patients. Nonetheless, allergen avoidance is not standard treatment and part of the reason is that there have been no controlled trials on asthma in the United States, and that the protocols for avoidance are not sufficiently well defined. The present D and E project will design and carry out a controlled trial of dust mite allergen avoidance in the treatment of children age 5 - 15 years presenting to hospital with asthma. The active protocol (n=3O) will involve aggressive measures in the child's bedroom; replacing carpeting; covering mattresses and pillows; and washing bedding weekly at 13O degrees F. The placebo group (n=3O) will receive placebo covers, a placebo carpet treatment and placebo air cleaners. Serum from the children will be assayed for IgE antibodies to common inhalant allergens especially dust mite, cat, dog and cockroach. The information on sensitization will not be available to physicians caring for the children. Thus, the actively treated group will include about 7O% mite allergic children and 3O% non-mite allergic children who will act as a second control group. These children will be followed for symptoms, requirements for medicine and bronchial reactivity to methacholine over 1 year. The study will be initiated at a suburban hospital in the Southeast, but we expect to involve more than one hospital. In parallel with this study a detailed educational plan will be developed with both written material and a 1O min. videotape to teach patients and parents about allergen avoidance. This teaching material will focus on establishing priorities and making firm written decisions with the patient. The protocol will be evaluated both by questionnaire and by assaying mite allergen levels in patients' houses. The objective is to establish a validated method for teaching avoidance to patients, together with controlled data to establish the effectiveness of a specific avoidance protocol.